Tool post for lathes



Nov. 4, 1952 R. H. BERGSTRM 2,616,325

Toor. PosT FOR LATHES Filed May 1s, 1949 2 sfmETs-SHEET 1 F/E.l

gf//f/@nuunn Nov. 4, 1952 R, H, BERGSTRM 2,616,326

l Toor. PosT FOR LATHEs Filed May 18, 1949 2 SHEETS- SHEET 2 'Patented Nov. 4, 1952 UNiTED STATES PATENTA OFFICE Application May 18, 1949, Serial No. 93,951 In Sweden September 29, 1948 4 Claims. (Cl. 82-36) This invention relates to tool posts which are to `be clamped, for instance, to the carriage of a lathe, and which are provided with means for clamping the tool holder to the post proper, said means including guide surf-aces adapted to cooperate with corresponding guide surfaces on the tool holder.

The invention has provide a tool post for lathes of this character which isof extremely durable construction.

Another object of the invention is to enable highly effective clamping action vto be obtained between the tool holder and the post, so that no vibration will occur between said parts.

Another object is to make provision for the tool post to resist greater loads than is the case with tool posts of the known construction where the tool holder is clamped to the post proper by an eccentric arrangement or the like.

For the objects stated, according to a particularly useful embodiment of the invention, the lower end of the screw for vertically adjusting the tool holder is supported by a shoulder projecting horizontally intermediate the guide surfaces of the tool holder. In this case such shoulder and also the lower end of the adjusting screw will be satisfactorily protected against chips etc.

Other objects and advantages will be apparent from the following description with reference to the accompanying drawings in which:

Fig. 1 is a side view of a toiol holder clamped to a post propel` mounted on the carriage of a lathe.

Fig. 2 is a plan view of the post proper and the tool holder.

Fig. 3 is an end view of the post and the tool holder shown partly broken away.

Fig. 4 is a lhorizontal View to a larger scale showing the tool holder and the adjacent portion of the post, the parts being shown partly in horizontal section.

Fig. 5 is a side View of the clamping means for the tool holder.

Fig. 6 is a frontal view of the latter.

The post proper I which, in the usual mannerl can be clamped to the carri-age 3 of a lathe, is provided on two adjacent sides with two pairs of guide members 4 the remotest lateral surfaces 5 of which are divergent in an outward direction and serve as guide surfaces cooperating with correspondingly shaped guide surfaces 6 of the vtool holder 'I. A wedge I0 is disposed in a recess 8 between the guides 4 and is displaceable therein by means of a screw 9. The wedge is for a principal object to provided with an arcuate recess II which is engaged by a peripherally extending collar I2 on lthe driving screw 9. In its edge surfaces the wedge I is provided with elongated grooves I3 engaged by the inner ends of two guide screws I4, respectively. The outer surface I of the wedge It is vertical, and the inner surface thereof I6 is preferably inclined about 10 relative to the vertical plane. The bottom of the recess 3 has the same inclination. The screw 9, having a square head I1 and being rotatable in one sense or the other by means oi' a handle I8 formed as a socket wrench, is threaded through a nut I9 inserted into the post I and having an extension the outer end portion of which projects into the recess 8. This outer end portion o1' the extensionl of the nut I9 forms a shoulder which is con-tac ted oy the lower end of an adjusting screw 2| passed through the tool holder I, said screw 2| being arranged to be slightly inclined in such a manner that its head zZ will be suniciently spaced :from the head I'I di' the screw t to en- -aoie both said screws to be conveniently operated. rlne inclination oi the adjusting screw ZI also involves the advantage that the inner wall 23 oi kthe tool hoider need not be boi-ed through. Thus no cnips'or the line can penetrate into. the space ze' into which the extension oi the nut Iii projects, and both the nut Iii and the lower end oi the screw ZI will be satisiactoriiy protected against damage. 'lhe turning tool 2b may be clamped to vthe tool holder 'i in a channel 2 therein by means of set screws in tne usual manner.

Owing to the fact that the adjusting screw 2| is situated approximately centrally between the guide surfaces on the to-ol holder l the holder, when slipped over the guide members d from above, and the lower end oi the adjusting Screw 2| nnaiiy contacts the snouider on the nut la, will necessarily adjust itseii' in the proper horizontal position. Thereafter, when the wedge It is displaced downward by means oi' the screw 9, the wedge will press its outer surrace against the inner surface of Ithe tool holder whereby 'the holder will be pressed straight outward so that the guide surfaces 6 of the same will engage the guide suriaces 5 on the post I. On account of the large contact area, the number of conta-ct surfaces being no less than six, and of the great force by which the Wedge I0 can be depressed, an exceptionally rrn clamping of the tool holder to the post proper will be obtained. Suiliciently firm clamp-lng can be obtained even if the tool holder 'I does not occupy its lowermost position,

as shown in Fig. 3. Satisfactory clamping will thus be obtained even if the holder be lowered only half-way over the guide members 4. Thereby it will be possible to have two tool holders simultaneously mounted 0.11 the post proper thus enabling two tools to be used for carrying out a turning operation.

By arranging the, extension. stille. mit. I9., shown in ljig, 6, to project through a dqwriwajrdlyff open recess 28 in the wedge I0, it will be possible to obtain sufficiently good guiding action for the, wedge In by forming the lateral surfaces of the" stud in such a manner that the side surfaces 2%.

of said recess will slide over thesanie. infinisy case no separate guiding will be 'necessary be' tween the side edges of the wedge` Maand the side surfaces of the recess 8.

It will be understood that the embodiment illustrated and described. in the foregoing' is" to' be Vconsidered merely as given by way ofY example, the'post proper tand thetool-"lfiolder` 1; as well as the means forfclamping the latter to the post L being capable ofbeing s'ifruc'tur all-y1varied'v in'several; ways without departing from the scope of invention.` The onlyessential thing residesv in giving', the guide surfaces Sand -6 such 'a shape that the clampingof the toolholder I is obtained by displacing thesa'mein an outward direction?. f `What l? claim and desire to secu-re'by- Letters Patentis:

1-. A tool postcomprising a post proper having means for clamping it to a support, a tool holder;

an adjusting screw for vertically adiu-stingj said toolholder relative to said post proper, guide surfaces on said post proper, Vco'rresp'onding' guide -Y surfaces on said tool holder and cooperating 'with saidL guide surfaces on saidpost proper upon ver-V tically adjusting said tool holder, all said' guide surfaces being parallel and' co-extensive with the sides of said post proper and saidV tool holder, a Wedge disposed between said post proper and said tool holder, andk a Yscrew for vertically mov-- ing said wedgein'one 'sense or the other, 'said wedge being adapted whenV moved*l downwards to press saidtool' holder outward for 'causing 'the guide surfaces or the latter to engage theguide surfaces of said post proper; an extension member partially extending into a recess in said post proper and disposed substantially centrally intermediate said guide surfaces on said tool holder and projecting into the path of motion of said adjusting screw for said tool holder, said extension having a threaded bore therein, said screw for vertically. moving saisi reds? being threaded and coactitig withsaid threaded borea'y collar on saidV threaded scr'w coac'tng" with said wedge for vertical movement thereof upon actuation of said screw coacting with said threaded bore, and a. Shauldenon. said extension forming a stop for the lowerend oisaid adjusting screw.

"'2`A"tool"as claimed in claim l, further eorriprigsinga vertically extending recess in said ,piostzDromer,v Said wedge being displaceable in said recess, said wedge being provided in its side edges with' two'oppositely disposed grooves extending longitudinally thereof, and two oppositely aligned gjide pins projecting fromv said post. proper, the inner ends of? said guide pins engaging said grooves for guidingsaidlwedge.

A'tool1.post.as claimedliin claim` 2,k further comprisinga transversely extending recess in said wedge, andsaid.v collar'beinerl peripherally are ranged on said screw and said recessbeingl en gagedby saidc'ollar. "4; 'A toolxpostl as: olaf-meet inc-Ianni', inL said adjusting screw isinclinedI in such a manner thatl its headwill-bey relatively Widely. spacedl from the-head of said wedgemovlingi screw.

BERGsf-IRr/r.-

REFERENCES CITED:

The following`- references are ,ofy record in the file vof this patent. UNITED PATENTS,...

Number-A Name Date 69.0.7263,. Parker: Jan. 7, i902: 'l5l,7:0;1 Tiff-'any1 Feb. 9, E904,

1;,959,1 40i.v Peterson May 1:5, 1934 2,14%,852 Bergstrom Feb.28;, 1.939.` 2,390,1:4i Y Hijmans Dec.` 4, 1,945. 2;4.03;405a Sirola July- 2f,L 1946. 

